Sunday, July 11, 2010

Cancer Sniffers Perform Better with Some Cancers than Others, but Testing Parameters Need More Standardization

Two scientists, one from the New College of Florida and one from the Pine Street Foundation in San Anselmo, reviewed the current state of canine cancer detection research, finding 531 potentially relevant articles, but focusing their analysis on five articles and one unpublished manuscript. The studies looked at canine detection of the following cancers:

1. Bladder cancer detection from smelling urine of patients, with 41% success rate (compared with 14% expected by chance).1 2. Melanoma detection by smelling lesions on patients, with a success rate between 75 and 85.7%.2 3. Lung and breast cancer by smelling samples of a patient’s exhaled breath,3 with a specificity of 99% and a sensitivity of 99%. The authors of the survey article explain that sensitivity is the proportion of cancer samples which the canines correctly identify, and specificity is the proportion of control samples which the canines correctly indicate as controls.4. Ovarian cancer by smelling ovarian tumor samples, with a sensitivity of 100% and a specificity of 97.5%.4 The researchers noted that the accuracy was remarkable given that some of the control tissues had been removed from areas adjacent to the tumor within the same patients. 5. Breast and prostate cancer by smelling urine samples in test tubes, with overall success rates that were not statistically significant.5 Another study, not analyzed because as yet unpublished, also failed to find significant results from dogs smelling urine of prostrate cancer patients. 6. Ovarian cancer by smelling exhaled breath condensate, with results not yet available.

The experiment involving breast and prostrate cancer was criticized by the authors of the review study for having different trainers using different methods, so that “inconsistencies in training may have made it nearly impossible for the dogs to perform well.” Storage conditions in the bladder cancer study varied, and dogs did considerably better when the urine sample was relatively fresh. The authors note that this study might have had insufficient controls, which might also have been true of the ovarian, breast, and prostrate cancer studies. The authors suggest also that there may be more cancer biomarkers at the source of the tumor and in exhaled breath than there are in urine.

The authors reaffirm their faith in using dogs as a diagnostic tool, but they emphasize the importance of additional research, as well as repeating studies already done. Mary Elizabeth Thurston suggested many years ago that cancer sniffers might be useful in poor countries (Lost History of the Canine Race).6 Much more research will be needed, however, before regular clinical use of cancer sniffers will become a reality. E. Moser and M. McCulloch (2010), Canine Scent Detection of Human Cancers: A Review of Methods and Accuracy. Journal of Veterinary Behavior, 5, 145-152.

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Novel About the First-Century Jewish Revolt Against Rome

Jacob Watts was a theologian, a distant relative on my mother's side who died while on a missionary assignment in India. Editing this book has been a long-term project. I can take credit for the maps, which show military actions for each year of the revolt that led to the destruction of the Jerusalem temple.

Novel About Rome in the Time of Nero

Four hundred slaves executed for a crime only one planned and committed, massive gladiatorial reenactments of famous battles, the great fire of Rome, murderous intrigue in the court of Nero, armies in revolt, astrologers who can change a person’s fate, the trial of St. Paul before the emperor—the reign of Nero was full of cinematic violence and color. Yet this is not a dress ball with modern characters who happen to wear tunics and togas. The power of the novel lies in the fact that as readers we enter the ancient mind at a time of social upheaval and religious transformation, bringing changes that echo across the centuries and become strangely relevant to events occurring in the world today.

Treatise on Money Laundering, Terrorism and Financial Institutions

John Ensminger is an attorney and member of the bars of the State of New York and the United States Supreme Court. He is the co-editor of Canine Olfaction Science and Law: Advances in Forensic Science, Medicine, Conservation, and Environmental Remediation. His other books include Police and Military Dogs: Criminal Detection, Forensic Evidence and Judicial Admissibility and Service and Therapy Dogs in American Society. His articles on legal and scientific issues have appeared in Applied Animal Behaviour Science, Forensic Science International, Journal of Forensic Sciences, Journal of Animal and Natural Resource Law, Journal of Veterinary Behavior, Journal of Animal Law, ABA General Practice, Tax Notes, and the Journal of Forensic Psychology Practice. John is a Contributing Editor of the Animal Legal & Historical Center of the Michigan State University College of Law.